The city’s Ethics Commission delivered the full record of its lengthy fact-finding inquiry into allegations of official misconduct to the Board of Supervisors, starting a 30-day countdown for supervisors to make a decision on whether Mirkarimi gets to keep his job.

The board is slated to take up the issue in a special meeting on Oct. 9. If it doesn’t make a decision in 30 days, the sheriff is automatically reinstated. Votes from at least nine of 11 supervisors would be needed for removal.

The last time San Francisco supervisors considered ousting another elected official was in 1932, when the then-public defender was indicted for murder and forced from office.

The mayor then filed official misconduct charges with the Ethics Commission, which under the City Charter is tasked with holding a fact-finding hearing and recommending whether the official misconduct charges should be sustained.

The commission, in a 4-1 vote on Aug. 16, found that Mirkarimi committed official misconduct as reflected in two of the mayor’s six charges, the first time since the commission was established in 1993 that it has completed such an inquiry.

On Tuesday, the commission transferred the record to the board — four volumes of large, three-ring binders per supervisor.